Low profile support frame and related intraluminal medical devices

ABSTRACT

A low profile support frame for use as an or in an expandable intraluminal medical device includes first and second wire members that define arcuate paths having opposing curves. Connectors join the wire members, and barbs can be disposed on the connectors. The support frame has radially compressed and radially expanded configurations. When the support frame is in the radially expanded configuration, substantially no portion of the support frame is disposed on a first transverse axis of the frame opposite one end of the frame and substantially no portion of the frame is disposed on a second transverse axis of the frame opposite the other end of the frame. The support frame can be used as an intraluminal medical device by itself or as a component in a medical device that includes other components, such as a stent, prosthetic valve, occluder, or filter.

RELATED APPLICATIONS

This non-provisional patent application is a continuation of U.S.Non-provisional patent application Ser. No. 12/711,915, filed on Feb.24, 2010 and which claims priority to U.S. Provisional PatentApplication No. 61/154,856, filed on Feb. 24, 2009. The entire contentsof each of these related applications are hereby incorporated byreference into this disclosure.

FIELD

The disclosure relates generally to the field of expandable intraluminalmedical devices. Particular embodiments relate to low profile supportframes for use in such medical devices. Additional embodiments relate toprosthetic valves, stents, filters, occluders, and other intraluminalmedical devices that incorporate one or more low profile support frames.

BACKGROUND

A variety of expandable intraluminal medical devices have been developedover recent years. For example, stents are routinely used in severalbody lumens as a means for providing support to ailing vessels, such ascoronary and non-coronary vessels. Occlusion devices are used tosubstantially block fluid flow through a body vessel, and prostheticvalves are used to regulate fluid flow through a body vessel. Bothprosthetic heart valves and venous valves have been the subject ofsignificant development efforts in recent years.

Expandable intraluminal medical devices are typically delivered to apoint of treatment using a delivery system designed for percutaneoustechniques. In a conventional procedure, a caregiver navigates thedelivery system through one or more body vessels until the expandableintraluminal medical device, which is typically contained in a distaltip of the delivery system, is positioned at or near the desired pointof treatment. Next, the caregiver deploys the expandable intraluminalmedical device from the delivery system, either by removing aconstraining force for self-expandable devices or by providing anexpansive force for balloon-expandable devices. Once deployment iscomplete, the delivery system is removed from the body vessel, leavingthe intraluminal medical device in an expanded configuration at thepoint of treatment. This delivery and deployment technique is largelyconventional and is used for most types of expandable intraluminalmedical devices, including stents, occluders, valves, and other types ofdevices.

During delivery, expandable intraluminal medical devices are maintainedin a compressed or reduced-diameter configuration within the deliverysystem to ensure navigability of the delivery system through the bodyvessel. The navigability of the delivery system is directly related toits overall outer diameter. A relatively large diameter limits theability of a delivery system to be navigated past curves, angles, sidebranch openings and other impediments, and also limits the ability of adelivery system to enter and/or be navigated through small diametervessels.

Because the delivery system must carry the intraluminal medical deviceto the point of treatment in the body vessel, efforts to minimize theouter diameter of delivery systems are necessarily confined by theability of the intraluminal medical device to be compressed. Thematerial, construction, and configuration of the medical device canlimit its ability to be compressed which, in turn, limits the useableouter diameter of the delivery system that will ultimately be used withthe device.

Some intraluminal medical devices, including some prosthetic valves andoccluders, include graft and/or valve members that add to the bulk ofthe support frame included in the device, compounding the difficultyassociated with increasing the compressibility of the device. A needexists, therefore, for low profile support frames that can be used inone or more such expandable intraluminal medical devices, eitherindependently of or in conjunction with other device components.Furthermore, a need exists for a variety of intraluminal medical devicesthat include a low profile support frame, including prosthetic valves,stents, filters, occluders, and the like.

BRIEF SUMMARY

Low profile support frames for use as or in expandable intraluminalmedical devices are described. A low profile support frame according toan exemplary embodiment comprises a first wire member having first andsecond ends and defining a first arcuate path with a first curvedisposed between the first and second ends; a second wire member havingthird and fourth ends and defining a second arcuate path with a secondcurve disposed between the third and fourth ends; a first connectorattached to the first and third ends; and a second connector attached tothe second and fourth ends. The first and second wire members form aclosed circumference that defines a closed cell, and the first connectoris spaced from the second connector along a longitudinal axis of thesupport frame.

In alternate embodiments, one or more of the first and second wiremembers comprises a series of curves that defines a path.

Expandable intraluminal medical devices that include a low profilesupport frame are also described. A prosthetic valve according to anexemplary embodiment comprises a support frame providing a closedcircumference defining a closed cell. The support frame includes a firstwire member having first and second ends and defining a first arcuatepath with a first curve disposed between the first and second ends, asecond wire member having third and fourth ends and defining a secondarcuate path with a second curve disposed between the third and fourthends, a first hollow connector disposed around the first and third ends,and a second hollow connector disposed around the second and fourthends. A valve member having first and second edges is attached to thesupport frame with at least a portion of the first edge attached to thesupport frame and the second edge being substantially free of thesupport frame and adapted to move between first and second positions.

A prosthetic valve according to another exemplary embodiment comprises afirst wire member having first and second ends and defining a firstarcuate path with a first curve disposed between the first and secondends; a second wire member having third and fourth ends and defining asecond arcuate path with a second curve disposed between the third andfourth ends; a first hollow connector disposed around the first andthird ends such that the first end is disposed on top of the third endwith respect to a plane containing the closed circumference; a secondhollow connector disposed around the second and fourth ends such thatthe second and fourth ends are disposed substantially side-by-side withrespect to the plane containing the closed circumference; and a valvemember having first and second edges, at least a portion of the firstedge attached to the support frame and the second edge beingsubstantially free of the support frame and adapted to move betweenfirst and second positions.

Additional understanding of the low profile support frames and variousintraluminal medical devices can be obtained with review of thefollowing detailed description and the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first exemplary support frame.

FIG. 1A is a cross-sectional view of the support frame illustrated inFIG. 1, taken along line 1A-1A.

FIG. 1B is a cross-sectional view of the support frame illustrated inFIG. 1, taken along line 1B-1B.

FIG. 1C is a cross-sectional view of an alternative support frame.

FIG. 2 is a partial sectional view of a body vessel in which the supportframe illustrated in FIG. 1 has been deployed.

FIG. 3 is a perspective view of a second exemplary support frame.

FIG. 4 is a perspective view of a third exemplary support frame.

FIG. 5 is a side view of an exemplary stent deployed in a common bileduct (illustrated in phantom).

FIG. 6 is a top view of a second exemplary stent deployed in a bodyvessel (illustrated in phantom).

FIG. 7 is a side view of the stent illustrated in FIG. 6.

FIG. 7A is a cross-sectional view of the stent illustrated in FIG. 6,taken along line 7A-7A.

FIG. 8 is a side view of a third exemplary stent deployed in a bodyvessel (illustrated in phantom).

FIG. 8A is a cross-sectional view of the stent illustrated in FIG. 8,taken along line 8A-8A.

FIG. 9 is a side view of a fourth exemplary stent deployed in a bodyvessel (illustrated in phantom).

FIG. 10 is a partial sectional view of a delivery system containing anexemplary stent.

FIG. 11 is a top view of a body vessel in which an exemplary prostheticvalve has been deployed.

FIG. 12 is a three-quarter view of a body vessel in which the prostheticvalve illustrated in FIG. 11 has been deployed. The valve is shown in aclosed configuration.

FIG. 12A is a cross sectional view of the body vessel illustrated inFIG. 12, taken along line 12A-12A.

FIG. 13 is a three-quarter view of a body vessel in which the prostheticvalve illustrated in FIG. 12 has been deployed. The valve is shown in anopen configuration.

FIG. 13A is a cross sectional view of the body vessel illustrated inFIG. 13, taken along line 13A-13A.

FIG. 14 is a perspective view of an exemplary support frame.

FIG. 15 is a top view of a body vessel in which an exemplary prostheticvalve has been deployed.

FIG. 16 is a three-quarter view of a body vessel in which the prostheticvalve illustrated in FIG. 15 has been deployed. The valve is shown in aclosed configuration.

FIG. 17 is a three-quarter view of a body vessel in which the prostheticvalve illustrated in FIG. 15 has been deployed. The valve is shown in anopen configuration.

FIG. 18 is a three-quarters view of a body vessel in which an exemplaryprosthetic valve has been deployed. The valve is shown in a closedconfiguration.

FIG. 19 is a three-quarters view of a body vessel in which an exemplaryprosthetic valve has been disposed. The valve is shown in an openconfiguration.

FIG. 20 is a perspective view of an exemplary occluder.

FIG. 21 is a cross-sectional view of a body vessel in which an exemplarysupport frame has been deployed.

FIG. 22 is a cross-sectional view of a body vessel in which an exemplaryprosthetic valve has been deployed. The valve is shown in a closedconfiguration.

DETAILED DESCRIPTION

The following detailed description and appended drawings describe andillustrate various exemplary embodiments of the invention. Thedescription and drawings serve to enable one skilled in the art to makeand use the inventive apparatuses, and are not intended to limit thescope of the invention or the protection sought in any manner.

FIGS. 1, 1A and 1B illustrate an exemplary support frame 10. The supportframe 10 includes first 12 and second 14 wire members. The first wiremember 12 includes a first end 12 a and a second end 12 b. The wiremember 12 defines an arcuate path 12 c that includes a curve 12 ddisposed substantially at a midpoint between the first 12 a and second12 b ends. Similarly, the second wire member 14 includes first 14 a andsecond 14 b ends and defines an arcuate path 14 c that includes a curve14 d disposed substantially at a midpoint between the ends 14 a, 14 b.

The wire members 12, 14 cooperatively define a closed circumference 16that, in turn, defines a single closed cell 18. A first connector 20 isdisposed at one end of the support frame 10 and a second connector 22 isdisposed at the opposite end of the support frame 10. The first ends 12a, 14 a of the first 12 and second wire 14 members are disposed withinthe first connector 20, and the second ends 12 b, 14 b of the first 12and second 14 wire members are disposed in the second connector 22. Eachof the connectors 20, 22 is attached to the appropriate ends 12 a, 12 b,14 a, 14 b to maintain the closed circumference 16 defined by the wiremembers 12, 14. While the connectors 20, 22 are illustrated as hollowmembers that receive the ends 12 a, 12 b, 14 a, 14 b of the wire members12, 14, it is understood that any suitable means for connecting wiremembers together can be used, including mechanical connections, such ascrimping, adhesives, a connection formed by annealing or brazing, or anyother suitable structure that provides a means for connecting wiremembers. The specific structure selected for the means for connectingthe wire members in a support frame according to a particular embodimentof the invention will depend on various considerations, including thematerials used in the wire members 12, 14.

It is noted that, while the support frame 10 is illustrated as beingformed of independent wire members connected to each other, the supportframe 10 can be formed of a unitary piece of material using suitabletechniques and materials. For example, the support frame could be cutfrom a tube of shape memory material using conventional or othersuitable techniques. For example, the support frame could be cut from atube of nitinol using laser cutting or other suitable techniques,followed by expansion and heat treatment steps that are known in theart. In these unitary embodiments, the wire members comprise struts inthe resulting structure and the connectors 20, 22 comprise joints atwhich individual struts are joined to each other. Connectors that areseparate and distinct from the struts are not necessary in theseembodiments—the joints perform the connecting function of the connectorsin these embodiments. Also, a single wire member could be used to formthe support frame using suitable bending techniques. In theseembodiments, bends in the wire member eliminate the need for connectors.It is noted, though, that in these embodiments, the inclusion of one ormore connectors might still be considered advantageous as a crimpingforce providing by the connector may maintain a bend in the single wiremember in a minimal thickness. It is also noted that a single wiremember having one end formed by a bend and the other end formed byattaching two independent ends of the single wire member can be used toform the support frame.

While the illustrated support frame 10 includes two wire members 12, 14,it is expressly understood that support frames can include any suitablenumber of wire members. It is noted, though, the inclusion of only twowire members is considered particularly advantageous at least becausetwo wire members, either as separate wire members, struts in a unitarystructure, or as a unitary wire formed into a support frame, is believedto provide the minimum structure needed to achieve the beneficialresults described herein, such as the minimal nature of the overall bulkof the support frame.

In the illustrated embodiment, each connector 20, 22 includes a closed24 and an open 26 end. The open end 26 is sized and configured toreceive the appropriate ends 12 a, 12 b, 14 a, 14 b. The closed end 24does not provide access to the inside of the connector 20, 22. A barb isadvantageously included on each of the connectors 20, 22. In thisembodiment, the barb 28 on the first connector 20 is disposed on asurface of the first connector 20 that faces in a substantially oppositedirection than the direction faced by the surface of the secondconnector 22 on which barb 30 is disposed, relative to a planecontaining the closed circumference 16 defined by the wire members 12,14. Also in this embodiment, the first barb 28 extends away from thefirst connector 20 in a direction that is different from the directionin which the second barb 30 extends away from the second connector 22.As illustrated in the figure, the barbs 28, 30 advantageously extend insubstantially opposite directions. This configuration is expected toprovide advantageous anchoring characteristics. It is noted that thebarbs 28, 30 are not necessarily drawn to scale relative to any othercomponent and/or element of the frame 10, and are shown as relativelylarge elements for illustrative purposes only.

As best illustrated in FIGS. 1A and 1B, pairs of the ends 12 a, 12 b, 14a, 14 b are advantageously positioned in their respective connectors 20,22 such that an imaginary line I.sub.1 containing the geometric centers(illustrated by dots) of ends 12 a, 14 a orients substantiallyorthogonally to an imaginary line I.sub.2 containing the geometriccenters (illustrated by dots) of ends 12 b, 14 b. Thus, when the frame10 is substantially flattened into a plane, as illustrated in FIG. 1,the first ends 12 a, 14 a are disposed with one end 14 a substantiallyon top of the other 12 a, relative to a plane containing the closedcircumference 16 defined by the wire members 12, 14. The second ends 12b, 14 b are disposed substantially side-by-side, relative to a planecontaining the closed circumference 16 defined by the wire members 12,14. Thus, a plane containing the geometric centers of ends 12 a, 14 a isdisposed substantially orthogonal to a plane containing the geometriccenters of ends 12 b, 14 b. This configuration of the ends 12 a, 12 b,14 a, 14 b is considered advantageous at least because it aids inmaintaining a desirable configuration of the closed cell 18 defined bythe closed circumference 16 following deployment of the support frame 10in a body vessel.

FIG. 1C illustrates an alternate arrangement for the first pair of ends12 a, 14 a. In this embodiment, the ends 12 a, 14 a define complimentarysemi-circular structures. This configuration minimizes the space neededwithin the connector 20 to contain the ends 12 a, 14 a, further reducingthe overall bulk of the support frame. This structure also eliminates orreduces the need to fill voids within the connector 20 (visible in FIG.1A) with filler material, such as solder or other material. Indeed, thisstructure can facilitate the use of purely mechanical means forattaching the connector 20 to the ends 12 a, 14 a, such as crimpedconnectors. In this embodiment, the entire wire members can define thecomplimentary shapes illustrated in FIG. 1C, or just the ends 12 a, 14 aor another longitudinal portion of the wire members can define thecomplimentary shapes, with the remainder of the wire members having around or other cross-section shape. Also, while FIG. 1C only illustratesone pair of ends 12 a, 14 a, it is understood that one or both pairs ofends can define complimentary shapes. Furthermore, one pair of ends candefine complimentary shapes, such as illustrated in FIG. 1C, while theother pair of ends has a different structure, such as illustrated inFIG. 1A or 113. Lastly, it is understood that, while FIG. 1C illustratessemi-circular complimentary shapes, it is understood that any suitableset of complimentary shapes can be used, including other mating shapes,interlocking shapes, and any other suitable shapes.

The frame 10 can be modified to include a structural member, such as oneor more of a ball, ring, hook, loop, or other suitable structural memberthat facilitates repositioning and/or retrieval of the frame within orfrom a body vessel using an appropriate catheter or other suitabledevice adapted to engage the structural member. The structural membercan be integrally formed with the frame 10 or one or both connectors 20,22 or can comprise a separately attached member. Furthermore, thestructural member can be positioned on the frame 10 at any suitablelocation. In one exemplary embodiment, a loop is formed on one connectoropposite the open cell defined by the wire members. A retrieval devicewith a hook can then be used to engage the loop to facilitaterepositioning and/or retrieval of the device.

FIG. 2 illustrates the support frame 10 disposed within a lumen 64 of abody vessel 60. The low profile nature of the support frame 10 can beseen immediately from this view. Upon deployment, the frame 10 adopts anexpanded configuration in which the first pair of ends 12 a, 14 a isspaced from the second pair of ends 12 b, 14 b on a lengthwise axisa.sub.1 of the frame 10. The first pair of ends 12 a, 14 a extends in afirst direction away from a structural midpoint of the support frame 10along the lengthwise axis al, while the second pair of ends 12 b, 14 bextends in a second, substantially opposite direction away from thestructural midpoint of the support frame 10 along the lengthwise axisa.sub.1. The first pair of ends 12 a, 14 a extends along an axis that isdifferent from, but substantially parallel to, the lengthwise axisa.sub.1 and the second pair of ends 12 b, 14 b extends along an axisthat is different from, but substantially parallel to, both thelengthwise axis a.sub.1 and the lengthwise axis of the first pair ofends 12 a, 14 a. Also, no portion of the support frame 10 is disposed ona transverse axis az opposite the first pair of ends 12 a, 14 a and/orthe first connector 20, and no portion of the support frame 10 isdisposed on a transverse axis a.sub.3 opposite the second pair of ends12 b, 14 b and/or the second connector 22. When deployed in a bodyvessel, as illustrated in FIG. 2, the wire members 12, 14, and thearcuate paths 12 c, 14 c defined by the members 12, 14, are insubstantially continuous contact with the inner surface of the wall 62of the body vessel 60. The first connector 20 and first pair of ends 12a, 14 a is in contact with a portion of the wall 62 of the body vessel60 that is substantially opposite the portion of the wall 62 with whichthe second connector 22 and the second pair of ends 12 b, 14 b is incontact.

As best illustrated in FIG. 2, the arcuate paths 12 c, 14 c and curves12 d, 14 d defined by the wire members 12, 14 position the connectors20, 22 and ends 12 a, 14 a, 12 b, 14 b in this manner upon adoption ofan expanded configuration and allow the support frame 10 to exert adesirable force on the body vessel 60, such as an outwardly-directedradial force, despite the minimal nature of the structure of the supportframe 10. The structure of the arcuate paths 12 c, 14 c and/or thecurves 12 d, 14 d, including the radius of curvature for the variousportions of the wire members 12, 14, can be varied and indeed optimizedfor particular support frames intended for particular uses. For example,the illustrated support frame 10 may be suitable for use as a stent, asdescribed below. An alternative support frame that positions the centralportion of the arcuate path 12 c, 14 c on a substantially transverseaxis to the lengthwise axis al of the support frame 10, upon expansion,is believed to be particularly advantageous for use in an occludermedical device that includes such a support frame. A skilled artisanwill be able to determine an appropriate structure of the arcuate pathsand/or curves for a support frame according to a particular embodimentbased on various considerations, including the nature of the body vesselin which the support frame is intended to be deployed, the nature offluid flow through the body vessel, and the nature and function of anyadditional components included in a medical device that includes thesupport frame.

The wire members 12, 14 can be formed of any suitable resilient materialacceptable for use in implantable medical devices. Examples of suitablematerials include, but are not limited to, stainless steel, nitinol,nickel-cobalt-chromium alloys, nickel-cobalt-chromium-molybdenum alloys,polymeric materials, and other biocompatible materials.Nickel-cobalt-chromium-molybdenum alloys, such as MP35N (CarpenterTechnology, Wyomissing, Pa.; MP35N is a registered trademark of SPSTechnologies, Inc.), are considered particularly advantageous at leastbecause of the relatively high tensile strength provided by thesematerials. As used herein, the term “wire member” does not refer to anyparticular size, diameter, or cross-sectional shape. While wire membershaving substantially circular cross-sectional shapes offer particularadvantages, they are not required. Examples of other suitablecross-sectional shapes include, but are not limited to, flat, square,triangular, D-shaped, trapezoidal, and delta-shaped cross-sectionalshapes. Also, as mentioned above, the support frame 10 can comprise aunitary member cut from an appropriate material, such as from a tube ofshape memory material. In these embodiments, the wire members comprisestruts in the structure resulting from the cutting process.

The connectors 20, 22 can be formed from the same material or adifferent material than that of the wire members 12, 14. Skilledartisans will be able to select appropriate materials for use in asupport frame 10 according to a particular embodiment of the inventionbased on various considerations, including the intended use, treatmentenvironment and manufacturing demands of the support frame 10. Theinventors have determined that wire members 12, 14 formed of nitinol andconnectors 20, 22 formed of stainless steel provide a support frame withdesirable characteristics for use in a variety of applications,including as a component in intraluminal medical devices, such asstents, prosthetic valves, and occluders.

FIG. 3 illustrates a support frame 10′ according to an alternativeembodiment. The frame 10′ is similar to the frame 10 illustrated in FIG.1, except as detailed below. Thus, the frame 10′ includes first 12′ andsecond 14′ wire members. The first wire member 12′ includes a first end12 a′ and a second end 12 b′, and the second wire member 14′ includes afirst end 14 a′ and a second end 14 b′. The wire members 12′, 14′cooperatively define a closed circumference 16′ that, in turn, defines asingle closed cell 18′. A first connector 20′ is disposed at one end ofthe support frame 10′ and a second connector 22′ is disposed at theopposite end of the support frame 10′. The first ends 12 a′, 14 a′ ofthe first 12′ and second wire 14′ members are disposed within the firstconnector 20′, and the second ends 12 b′, 14 b′ of the first 12′ andsecond 14′ wire members are disposed in the second connector 22′. Eachof the connectors 20′, 22′ is attached to the appropriate ends 12 a′, 12b′, 14 a′, 14 b′ to maintain the closed circumference 16′ defined by thewire member 12′, 14′.

In this embodiment, the first wire member 12′ comprises a first series70 a′ of curves 72 a′ that define a first serpentine path 74 a′, and thesecond wire member 14′ comprises a second series 70 b′ of curves 72 b′that define a second serpentine path 74 b′. While the frame 10′ isillustrated with both wire members 12′, 14′ defining serpentine paths,it is understood that a frame can be constructed with only one of thewire members defining a serpentine path without departing from the scopeof the invention. In these alternative embodiments, the wire member notdefining a serpentine path can have any suitable configuration,including an arcuate path as described and illustrated in regards to theembodiment illustrated in FIG. 1.

The inclusion of a series of curves that define a serpentine path isconsidered advantageous at least because this configuration is expectedto increase the radial expandability and stability of the support frame10′.

FIG. 4 illustrates a support frame 10″ according to another alternativeembodiment. The frame 10″ is similar to the frame 10 illustrated in FIG.1, except as detailed below. Thus, the frame 10″ includes first 12″ andsecond 14″ wire members. The first wire member 12″ includes a first end12 a″ and a second end 12 b″, and the second wire member 14″ includes afirst end 14 a″ and a second end 14 b″. The wire members 12″, 14″cooperatively define a closed circumference 16″ that, in turn, defines asingle closed cell 18″. A first connector 20″ is disposed at one end ofthe support frame 10″. The first ends 12 a″, 14 a″ of the first 12″ andsecond wire 14″ members are disposed within the first connector 20″.

In this embodiment, the first wire member 12″ comprises a first series70 a″ of curves 72 a″ that define a first serpentine path 74 a″, and thesecond wire member 14″ comprises a second series 70 b″ of curves 72 b″that define a second serpentine path 74 b″. Each of the wire members12″, 14″ also includes one or more curves 76″ disposed along the lengthon an interconnecting section 78″ between curves 72 a″, 72 b″ of theseries 70 a″, 70 b″ of curves. The curves 76″ can comprise curvilinearcurves, as illustrated, angulated, or other curves, but do not comprisecurves that substantially after the path of the interconnecting section78″. The inclusion of such curves is considered advantageous at leastbecause they provide a flexing zone to the interconnecting sections 78″that allow the frame 10″ to better conform to a tortuous duct or vessel.The inclusion of curves 76″ is also expected to facilitate deployment ofthe frame 10″, or an intraluminal medical device including the frame10″, from side-viewing endoscopes, which have an acute delivery angle.

While the support frames described herein are considered usefulindependent of additional components, as an intraluminal stent, forexample, the frames are also useful as a platform onto which othercomponents and or functionalities can be added to provide new and usefulintraluminal medical devices of various types, such as stents,prosthetic valves, occluders, filters, and the like. Various examples ofsuch devices are described below.

The inventive support frames can be used as a component in a removeablebiliary stent. Current plastic biliary stents last only about six monthsbefore becoming clogged and requiring removal and/or replacement. Thus,there is a need for a stent that is less likely to become clogged. Thelow profile nature of the inventive support frames make them well-suitedfor this application. In these embodiments, the wire members of theframe advantageously can be coated and/or encased in a polymer, such asThoralon or another suitable polymer, to prevent cells/tissue fromgrowing over the wire members, which could hinder retrieval and/orremoval of the stent. Alternatively, the stent could be used as a shortterm measure to dilate the duct to allow passage or removal of a largerstone or calculi such that the polymer wouldn't be necessary. The stentcould even be used to capture the stone and retain it while beingremoved from the duct, thereby removing the stone. In placing thesestents in the common bile duct (or pancreatic duct), the proximal pairof ends of the support frame would extend from the Papilla of Vater intothe duct, allowing the stent to be retrieved and removed underendoscopic viewing. These stents can be delivered from a sheath ordirectly from the accessory channel of a duodenoscope if it is placedclose enough to the papilla to limit expansion until the stent wasdeployed within the duct. Trigger wires or constraining sutures can beused to control expansion during deployment. The connector joining theends of the support frame wire members that is inserted into the ductmay be shaped to aid in cannulation of the papilla, or it may include apassageway to allow the stent to be introduced into the duct over a wireguide used for the cannulation of the papilla.

It is noted that, while the support frames are described as being usefulin stents intended for placement in certain bodily ducts and vessels,such as the common biliary duct and other ducts of the biliary tract,the frames, and indeed the devices that include the frames, can be usedin any suitable bodily duct, passage, vessel or other location in needof a benefit provided by the support frame or medical device, such as astenting function, a valving function, an occlusion function, or anyother benefit provided by the support frame or medical device asappropriate. For example, the stents described herein could be adaptedfor use as urethral stents without departing from the scope of theinvention. Also, the prosthetic valves described herein could be adaptedfor use as prosthetic venous valves and prosthetic heart valves withoutdeparting from the scope of the invention.

FIG. 5 illustrates an exemplary stent 80 positioned within a common bileduct 81 of an animal, such as a human. The stent 80 is similar tosupport frame 10 illustrated in FIG. 1, but includes first 82 a andsecond 82 b serpentine sections formed by bends in each of the wiremembers 83 a, 83 b. The first connector 84 is an elongate structuredefining a tapered atraumatic tip which adapts the connector 84 forcannulation of the papilla during deployment of the biliary stent 80.The second connector 85 includes an outwardly-extending flap 86 thatengages the major papilla during placement, which prevents the stent 80from being completely inserted into the common bile duct 81 duringplacement and aids in retrieval of the stent 80. A loop 87 extends fromthe proximal end of the second connector 85, providing a structure thatcan be engaged by a suitable catheter-based or other tool for retrievalof the stent 80 from the duct 81.

As illustrated in the figure, the serpentine sections 82 a, 82 b can bepositioned in contact with the duct wall across a stricture 88 therein.This positioning is considered advantageous because it is believed thatthe increased radial strength in the region of the stent 80 thatincludes the serpentine sections 82 a, 82 b will aid in maintaining thepatency of the duct 81 at the stricture. It is noted that while theserpentine sections 82 a, 82 b are illustrated as being positionedsubstantially in the longitudinal middle of the stent 80, they can bepositioned at any point along the length of the stent 80. Indeed, theserpentine sections 82 a, 82 b can be positioned in a custom location ona stent 80 that is based on a known or expected location of a specificstricture within a specific duct of a specific animal. Furthermore,while two serpentine sections 82 a, 82 b are illustrated, it is notedthat any suitable number of serpentine sections can be included,including a series of serpentine sections such as illustrated in FIGS. 3and 4. Also, each wire member can include any suitable number ofserpentine sections, including zero, and the wire members need not havethe same number of serpentine sections.

FIGS. 6, 7 and 7A illustrate another exemplary stent 90 positionedwithin a body vessel 91 of an animal, such as a human. Stent 90 issimilar to the stent 80 illustrated in FIG. 5, except that the wiremembers do not include serpentine sections. Thus, the stent 90 includesa first connector 92 that is an elongate structure defining a taperedatraumatic tip and a second connector 93 that includes anoutwardly-extending flap 94. In this embodiment, multiple loops 95extend from the proximal end of the second connector 93, providingmultiple structures that can be engaged by a suitable retrieval tool.The inclusion of multiple loops is considered advantageous becausemultiple loops provide multiple structures that can be engaged duringretrieval, which is expected to increase the ease with which the stent90 can be retrieved from the vessel 91.

FIG. 7A illustrates the spacing of the wire members 96 a, 96 b near thesecond connector 93.

FIGS. 8 and 8A illustrate an alternative structure for stent 90. In thisembodiment, the stent 90 includes a stabilizing member 96 that extendsalong an axis that is substantially parallel to a lengthwise axis of thestent 90. A proximal end of the stabilizing member 97 is containedwithin the second connector 93 along with the ends of the wire members96 a, 96 b, and a distal end of the stabilizing member 96 is free ofcontact with other portions of the stent 90. As illustrated in thefigure, the stabilizing member 97 provides a structural member thatextends along the wall of the duct 91, providing additional contact areabetween the stent 90 and the wall. It is believed that this additionalcontact area will enhance the ability of the stent 90 to maintainpatency of the duct 91.

Comparing FIGS. 7A and 8A reveals a benefit of a stabilizing member thatextends to the second connector 93. As illustrated in FIG. 8A, astabilizing member 97 positioned in this manner provides a third pointof support to aid in maintaining patency of the duct or body vessel nearthe second connector 93 and proximal end of the support frame. Inbiliary stent embodiments, this portion of the support frame istypically positioned near the sphincter of Odii, which controls the flowof digestive juices out of the biliary tract. The inclusion of astabilizing member positioned in this manner in a biliary stentembodiment therefore, provides a third point of contact with thesphincter and is expected to enhance drainage of the duct followingplacement of the stent, which may reduce the likelihood that the stentwill become clogged and/or lengthen the time it takes for the stent tobecome clogged.

Any suitable structure can be used for the stabilizing member 97,including a single wire member, a looped wired member (as illustrated inFIGS. 8 and 8A), and any other suitable structure. A looped member isconsidered advantageous at least because the loop can be formed toinclude a rounded edge, which will be less likely to engage and/orpierce the duct wall than a simple blunt end of a single wire member.Furthermore, the distal end of the stabilizing member 96, no matter thestructure used, can be coated or embedded within a material, such as aplastic or gel, that provides a desired atraumatic tip for the distalend.

FIG. 9 illustrates an alternative stabilizing member 97′. In thisembodiment, the stabilizing member is connected to the wire members 96a, 96 b at a point between the first 92 and second 93 connectors. Asimple cannula or other suitable connection can be used to form thisconnection, or the stabilizing member 97′ can be integrally formed withthe wire members 96 a, 96 b. In this embodiment, the stabilizing member97′ is a loop structure that includes first 98 a and second 98 b bendsthat, in conjunction with the distal loop 98 c, define first 99 a andsecond 99 b s-curves. This structure is expected to provide desirableradial strength characteristics while not adding significantly to theoverall bulk of the stent 90.

It is noted that, while the illustrated biliary stents include a flapstructure for engaging the papilla during placement, any suitableretention structure that mechanically prevents the biliary stent frombeing completely advanced into the biliary duct can be used, includingmultiple flaps, pigtails, balloons, and the like. It is also noted that,if prevention of migration at the opposite end of the stent is desired,one or more suitable retention structures can be placed on the distalend of the stent as well, either in addition to or in place of the flapor other retention structure positioned at the proximal end of thestent.

FIG. 10 illustrates the stent 90 of FIGS. 6 and 7 placed within adelivery system 101. The stent 90 is in a compressed configuration andcircumferentially surrounded by a sheath 102. The loop 95 is engagedwith a corresponding loop 103 on an inner member 104 of the deliverysystem 101. A guidewire 105 passes through exchange port 106 and througha passageway 107 defined by the first connector 92, allowing the stent90 to be placed using guidewire-based delivery and deploymentprocedures. It is noted that, while the illustrated delivery system 101is adapted for rapid-exchange or short wire applications, a conventionover-the-wire delivery system could also be used. In these embodiments,the second connector 93 can also define a passageway through which theguidewire can pass.

FIGS. 11, 12, 12A, 13, and 13A illustrate a prosthetic valve device 100according to an exemplary embodiment of the invention. The prostheticvalve device 100 includes a support frame 110 and an attached valvemember 150. In each of the figures, the valve device is disposed withina body vessel 160. The body vessel 160 has a wall 162 and defines alumen 164.

The support frame 110 is similar to the support frame 10 illustrated inFIG. 1 and described above. Thus, the support frame 110 includes first112 and second 114 wire members. The first wire member 112 includes afirst end 112 a and a second end 112 b. The wire member 112 defines anarcuate path 112 c that includes a curve 112 d disposed substantially ata midpoint between the first 112 a and second 112 b ends. Similarly, thesecond wire member 114 includes first 114 a and second 114 b ends anddefines an arcuate path 114 c that includes a curve disposedsubstantially at a midpoint between the ends 114 a, 114 b. The wiremembers 112, 114 cooperatively define a closed circumference 116 that,in turn, defines a single closed cell 118. A first connector 120 isdisposed at one end of the support frame 110 and a second connector 122is disposed at the opposite end of the support frame 110. The first ends112 a, 114 a of the first 112 and second 114 wire members are disposedwithin the first connector 120, and the second ends 112 b, 114 b of thefirst 112 and second 114 wire members are disposed in the secondconnector 122.

Each of the connectors 120, 122 is attached to the appropriate ends 112a, 112 b, 114 a, 114 b and includes a closed 124 and an open 126 end.Pairs of the ends 112 a, 112 b, 114 a, 114 b are disposed in the openend 126 of the appropriate connector 120, 124. A first barb (notillustrated in FIG. 11) is disposed on the first connector 120 and asecond barb 130 on the second connector 122, substantially opposite tothe first barb. It is noted that the barbs are not necessarily drawn toscale relative to any other component and/or element of the frame 110,and are shown as relatively large elements for illustrative purposesonly.

The valve member 150 comprises a section of material, such as a sheet,that is attached to the support frame 110. The valve member 150 can beformed of any suitable material, and need only be biocompatible or beable to be rendered biocompatible. The material can advantageously beformed of a flexible material. Examples of suitable materials for thevalve member 150 include natural materials, synthetic materials, andcombinations of natural and synthetic materials. Examples of suitablenatural materials include extracellular matrix (ECM) materials, such assmall intestine submucosa (SIS), other bioremodellable materials, andfixed natural tissues, such as fixed bovine pericardium. Other examplesof ECM materials that can be used in the prosthetic valves of theinvention include stomach submucosa, liver basement membrane, urinarybladder submucosa, tissue mucosa, and dura mater. Tissue valves andportions thereof, such as a leaflet, patch, or other suitable portion ofa tissue valve, can also be used. One or more sections of dermis, suchas porcine and cadaveric dermis, can also be used as the valve member.ECM materials are particularly well-suited materials for use in thevalve member 150, at least because of their abilities to remodel andbecome incorporated into adjacent tissues. These materials can provide ascaffold onto which cellular in-growth can occur, eventually allowingthe material to remodel into a structure of host cells. Examples ofsuitable synthetic materials include polymeric materials, such asexpanded polytetrafluoroethylene and polyurethane. The use of syntheticmaterials also allows the valve member to be formed as a web spanningappropriate portions of the support frame 110, such as by spraying,dipping or other suitable techniques for forming a webbing betweenstructural members.

The valve member 150 includes a free edge 152 that is not attached tothe support frame 110 and at least one portion 154 that is attached tothe support frame by in any suitable manner, such as sutures 156.Alternatively, the valve member 150 can be attached to the support frame110 by other means for attaching, such as adhesives, a heat seal, atissue weld joint, a weave, or any other suitable means for attaching avalve member to a portion of a support frame. The specific means forattaching chosen will depend at least upon the materials used in thevalve member 150 and the support frame 110, and a skilled artisan willbe able to determine appropriate structure for a valve device accordingto a particular embodiment of the invention.

Alternatively, the one or both of the wire members 112, 114 can bepassed into and/or through one or more portions of the valve member 150to create an attachment between the support frame 110 and valve member150. For example, one or both of the wire members 112, 114 can beinserted into a thickness of a portion of the valve member 150, such asan associated patch of tissue, extended along a length thereof andeventually passed back out of the thickness. This “tunneling through” aportion of the valve member may provide an attachment that eliminatesthe need for sutures or other attachment members, and is consideredsuitable for use in valve devices having valve members that provide anacceptable thickness that is able to accommodate the wire members 112,114. Skilled artisans will be able to determine if this alternativeattachment is suitable for any given valve member based on variousconsiderations, including the thickness of the material of the valvemember and the diameter or other relevant dimension of the wire members112, 114. Valve members comprising fixed natural tissue are consideredsuitable for this approach. If this approach is used, the wire members112, 114 can be passed into and through a portion of the valve memberand subsequently connected together by applying one of the connectors120, 124 to the wire members 112, 114. Also, the portion of the wiremembers 112, 114 that is expected to remain within the thickness of thevalve member 150 can include structural adaptations that enhance theattachment between the support frame 110 and the valve member 150, suchas microbarbs as described elsewhere herein.

As illustrated in FIG. 11, two lateral portions 154, 155 of the valvemember 150 are advantageously attached to the support frame by wrappingthe edges of the valve member 150 around the wire members 112, 114. Alsoadvantageously, the valve member 150 is sized and configured to extendfrom a point at which the wire members 112, 114 overlap and/or toucheach other to the curve 112 d, 114 d associated with each member 112,114. Extending the valve member 150 to this length is expected toenhance the durability of the attachment between the valve member 150and the support frame 110 under dynamic in vivo conditions.Alternatively, the valve member 150 can be sized and configured toextend from a point at which the wire members 112, 114 overlap and/ortouch each other to a point beyond the curve 112 d, 114 d associatedwith each member 112, 114.

As described in more detail below, the free edge 152 is moveable betweenfirst and second positions when the device 100 is placed within a bodyvessel. The valve member 150 includes slack 158 between the wire member112, 114 that facilitates this movement of the free edge 152.

The prosthetic valve device 100 is adapted to be disposed in a bodyvessel 160 using percutaneous delivery techniques. The body vessel 160can be any suitable body vessel, including any vessel of thevasculature, such as veins, arteries, and sections of the heart. Thus,the vessel 160 illustrated in the figures is illustrative only; thebasic structure should not be interpreted as limiting the types ofvessels in which the device can be deployed. As such, the vessel 160includes a vessel wall 162 and defines a lumen 164 in which the valvedevice 100 is disposed.

FIGS. 12 and 12A illustrate the valve device 100 in a closedconfiguration while FIGS. 13 and 13A illustrate the valve device 100 inan open configuration. The valve device 100 is secured in the bodyvessel by the first barb 128, which passes into the vessel wall 162 at afirst point 166, and the second barb 130, which passes into the vesselwall 162 at a second point 168. It is noted that the barbs 128, 130 arenot necessarily drawn to scale. Indeed, microbarbs that only partiallypass into the thickness of the vessel wall 162 may be used. Furthermore,a series of two or more microbarbs can be used at each barb 128, 130location. The barbs 128, 130 are illustrated as penetrating through theentire thickness of the vessel wall only to facilitate understanding ofthe operation of the valve device 100 and is not required. Furthermore,a series of two or more microbarbs can be used at each barb 128, 130location.

Also, the barbs 128, 130 can have shape memory properties of their ownthat facilitate anchoring of the valve device 100 in the body vessel.For example, the barbs 128, 130 can adopt an “open” configuration atroom temperature and a “clamped” or “closed” configuration at anothertemperature, such as the expected or actual body temperature of theanimal, such as a human, into which the valve device is being implanted.In the open configuration, a clearance exists between the barb and theunderlying connector 120, 122 and/or wire member 112, 114. In theclamped or closed configuration, the clearance is reduced. Thus, whenthe transition temperature is reached, the barb 128, 130 moves closer tothe connector 120, 122 and/or wire member 112, 114, which can clamp aportion of the vessel wall 162 between the barb 128, 130 and theconnector 120, 122 and/or wire member 112, 114. This is expected toenhance anchoring of the valve device 100 in the body vessel 160.

As described above, the valve member 150 is moveable between first andsecond positions when the device 100 is placed within a body vessel 160.In the first position, illustrated in FIG. 12, the valve member 150substantially prevents fluid flow in the direction represented by arrow185 from flowing past the point in the body vessel 160 at which thevalve device 100 is deployed. In the second position, illustrated inFIG. 13, the valve member 150 permits fluid flow in an oppositedirection, represented by arrow 175, to flow through the closed cell 118defined by the closed circumference 116. The valve member 150 moves tothe first position when a pressure change and/or reversal of flowdirection exerts a force on an edge or face of the valve member 150 andforces it away from the vessel wall 162 and across the lumen 164 of thevessel 160. The valve member 150 moves to the second position when apressure change and/or reversal of flow direction exerts a force on anopposing edge or face of the valve member 150, forcing it toward vesselwall 161. The first position of the valve member 150 can be considered aclosed position, and the second position can be considered an openposition. By moving between these two positions, the valve member 150provides a valving function to the medical device 100, allowing it toregulate fluid flow through the body vessel 160.

As illustrated in FIGS. 12 and 12A, the valve member forms a pocket 159that collects fluid, substantially preventing passage through the closedcell 118 defined by the closed circumference 116 during periods ofretrograde flow in which the valve member 150 is in the closed position.As best illustrated in FIGS. 13 and 13A, the valve member 150 is forcedtoward a portion of the vessel wall 162 (upward in the Figure) duringperiods of antegrade flow 175, thereby adopting the open position andallowing fluid to flow through the closed cell 118 defined by the closedcircumference 116.

The medical device 100 illustrated in FIGS. 11 through 13 is aprosthetic valve, and can be used as a prosthetic venous valve. In thiscapacity, the device 100 is placed in a vein to regulate the flow ofblood through the vein. It is believed that the valve member 150 movesto the open position, illustrated in FIG. 13, during systole in whichthe heart forces blood through the vein in the first direction 175.During diastole, the valve member 150 moves to the closed position,illustrated in FIG. 12, to substantially prevent fluid flow in thesecond, opposite direction 185. It is believed that a pressure changeand reversal of flow direction occurs during the change from systole todiastole, and the valve member 150 changes position in response to thesechanges. Flow in the second, opposite direction 185 is commonly referredto as retrograde flow.

The valve member 150 substantially, but not entirely, prevents fluidflow in the second, opposite direction 185 for at least two reasons.First, as the valve member 150 moves from the first position to thesecond position, a time period passes before the valve member is in thesecond position, and some retrograde flow may pass through the device100 during this time. Second, as best illustrated in FIGS. 12 and 12A,the valve member 150 does not form a complete and constant seal with thevessel wall 162 while in the second or closed position.

FIG. 14 illustrates a support frame 210 according another exemplaryembodiment of the invention. The support frame 210 according to thisembodiment is similar to the support frame 10 illustrated in FIG. 1 anddescribed above, except as detailed below. Thus, the support frame 210includes first 212 and second 214 wire members. The first wire member212 includes a first end 212 a and a second end 212 b. The wire member212 defines an arcuate path 212 c that includes a curve 212 d disposedsubstantially at a midpoint between the first 212 a and second 212 bends. Similarly, the second wire member 214 includes first 214 a andsecond 214 b ends and defines an arcuate path 214 c that includes acurve disposed substantially at a midpoint between the ends 214 a, 214b. The wire members 212, 214 cooperatively define a closed circumference216 that, in turn, defines a single closed cell 218. A first connector220 is disposed at one end of the support frame 210 and a secondconnector 222 is disposed at the opposite end of the support frame 210.The first ends 212 a, 214 a of the first 212 and second 214 wire membersare disposed within the first connector 220, and the second ends 212 b,214 b of the first 212 and second 214 wire members are disposed in thesecond connector 222.

Each of the connectors 220, 222 is attached to the appropriate ends 212a, 212 b, 214 a, 214 b and includes a closed 224 and an open 226 end.Pairs of the ends 212 a, 212 b, 214 a, 214 b are disposed in the openend 226 of the appropriate connector 220, 224. A first barb (notillustrated in FIG. 14) is disposed on the first connector 220 and asecond barb 230 on the second connector 222, substantially opposite tothe first barb. It is noted that the barbs are not necessarily drawn toscale relative to any other component and/or element of the frame 210,and are shown as relatively large elements for illustrative purposesonly.

The support frame 210 according to this exemplary embodiment includesfirst 240 and second 242 support arms. The support arms 240, 242 provideadditional surface area to the support frame 210 that can provideadditional contact area between the support frame 210 and a wall of avessel in which the frame 210 or an associated device is deployed.Furthermore, each of the support arms 240, 242 defines a loop that canbe engaged by another medical device, such as a retrieval hook or otherdevice adapted to engage one or both of the arms 240, 242, to enablerepositioning and/or retrieval of the support frame 210, or a medicaldevice that includes the support frame 210, following deployment.

Each of the support arms 240, 242 is attached to the respective wiremember 212, 214. Alternatively, one or both of the support arms 240, 242can be integrally formed by the respective wire member 212, 214.

The first support arm 240 is a closed circumference 243 a defined byfirst 244 a and second 245 a lengths that extend away from the firstwire member 212 and a curve 246 a disposed between the first 244 a andsecond 245 b lengths. The closed circumference 243 a defines an opening247 a between the first 244 a and second 245 a lengths and the curve 246a.

The second support arm 242 is a closed circumference 243 b defined byfirst 244 b and second 245 b lengths that extend away from the secondwire member 214 and a curve 246 b disposed between the first 244 b andsecond 245 b lengths. The closed circumference 243 b defines an opening247 b between the first 244 b and second 245 b lengths and the curve 246b.

FIGS. 15 through 17 illustrate a valve device 300 according to anotherexemplary embodiment of the invention. The valve device 300 of thisembodiment is similar to the valve device 100 illustrated in FIG. 11 anddescribed above, except as detailed below. In each of the figures, thevalve device is disposed within a body vessel 360. The body vessel 360has a wall 362 and defines a lumen 364.

The valve device 300 according to this embodiment includes a supportframe 310 similar to the support frame 210 illustrated in FIG. 14 anddescribed above, and an attached valve member 350. The support frame 310includes first 312 and second 314 wire members. The first wire member312 includes a first end 312 a and a second end 312 b. The wire member312 defines an arcuate path 312 c that includes a curve 312 d disposedsubstantially at a midpoint between the first 312 a and second 312 bends. Similarly, the second wire member 314 includes first 314 a andsecond 314 b ends and defines an arcuate path 314 c that includes acurve disposed substantially at a midpoint between the ends 314 a, 314b. The wire members 312, 314 cooperatively define a closed circumference316 that, in turn, defines a single closed cell 318. A first connector320 is disposed at one end of the support frame 310 and a secondconnector 322 is disposed at the opposite end of the support frame 310.The first ends 312 a, 314 a of the first 312 and second 314 wire membersare disposed within the first connector 320, and the second ends 312 b,314 b of the first 312 and second 314 wire members are disposed in thesecond connector 322.

Each of the connectors 320, 322 is attached to the appropriate ends 312a, 312 b, 314 a, 314 b and includes a closed 324 and an open 326 end.Pairs of the ends 312 a, 312 b, 314 a, 314 b are disposed in the openend 326 of the appropriate connector 320, 324. A first barb (notillustrated in FIG. 15) is disposed on the first connector 320 and asecond barb 330 on the second connector 322, substantially opposite tothe first barb. It is noted that the barbs are not necessarily drawn toscale relative to any other component and/or element of the frame 310,and are shown as relatively large elements for illustrative purposesonly.

The support frame 310 includes first 340 and second 342 support armsattached to or formed by the respective wire member 312, 314. The firstsupport arm 340 is a closed circumference 343 a defined by first 344 aand second 345 a lengths that extend away from the first wire member 312and a curve 346 a disposed between the first 344 a and second 345 blengths. The closed circumference 343 a defines an opening 347 a betweenthe first 344 a and second 345 a lengths and the curve 346 a.

The second support arm 342 is a closed circumference 343 b defined byfirst 344 b and second 345 b lengths that extend away from the secondwire member 314 and a curve 346 b disposed between the first 344 b andsecond 345 b lengths. The closed circumference 343 b defines an opening347 b between the first 344 b and second 345 b lengths and the curve 346b.

The valve member 350 includes a free edge 352 that is not attached tothe support frame 310 and at least one portion 354 that is attached tothe support frame 310 in any suitable manner, such as sutures 356.Preferably, as illustrated in the figures, the valve member 350 isattached to the support frame along attachment pathways defined by thefirst 340 and second 342 support arms. The free edge 352 is moveablebetween first and second positions when the device 300 is placed withina body vessel. The valve member 350 can include slack between the wiremember 312, 314 that facilitates this movement of the free edge 352.

The prosthetic valve device 300 is adapted to be disposed in a bodyvessel 360 using percutaneous delivery techniques. The vessel 360includes a vessel wall 362 and defines a lumen 364 in which the valvedevice 300 is disposed. FIG. 16 illustrates the valve device 300 in aclosed configuration and FIG. 17 illustrates the valve device 300 in anopen configuration. The valve device 300 is secured in the body vessel360 by the first barb 328, which passes through the vessel wall 362 at afirst point 366, and the second barb 330, which passes through thevessel wall 362 at a second point 368.

The valve member 350 moves between the first and second positionssimilar to the manner in which the valve member 150 illustrated in FIGS.12 and 13 does so. In this embodiment, though, the support arms 340, 342limit the movement the valve member can make toward the vessel wall whenthe valve member 350 moves to the second position. Furthermore, thesupport arms 340, 342 provide support to the valve pocket when the valvemember 350 is in the open position, which is expected to aid inprevention eversion of and/or damage to the valve member 350.

FIG. 20 illustrates an occluder 400 according to an embodiment of theinvention. The occluder 400 includes a support frame 410 according to anembodiment of the invention and a graft member 490 attached to thesupport frame 410.

The support frame 410 is similar to the support frame 10 illustrated inFIG. 1 and described above. Thus, the support frame 410 includes first412 and second 414 wire members. The first wire member 412 includes afirst end 412 a and a second end 412 b. The wire member 412 defines anarcuate path 412 c that includes a curve 412 d disposed substantially ata midpoint between the first 412 a and second 412 b ends. Similarly, thesecond wire member 414 includes first 414 a and second 414 b ends anddefines an arcuate path 414 c that includes a curve 414 d disposedsubstantially at a midpoint between the ends 414 a, 414 b. The wiremembers 412, 414 cooperatively define a closed circumference 416 that,in turn, defines a single closed cell 418. A first connector 420 isdisposed at one end of the support frame 410 and a second connector 422is disposed at the opposite end of the support frame 410. The first ends412 a, 414 a of the first 412 and second 414 wire members are disposedwithin the first connector 420, and the second ends 412 b, 414 b of thefirst 412 and second 414 wire members are disposed in the secondconnector 422.

Each of the connectors 420, 422 is attached to the appropriate ends 412a, 412 b, 414 a, 414 b and includes a closed 424 and an open 426 end.Pairs of the ends 412 a, 412 b, 414 a, 414 b are disposed in the openend 426 of the appropriate connector 420, 424. A first barb (notillustrated in FIG. 20) is disposed on the first connector 420 and asecond barb 430 on the second connector 422, substantially opposite tothe first barb. It is noted that the barbs are not necessarily drawn toscale relative to any other component and/or element of the frame 410,and are shown as relatively large elements for illustrative purposesonly.

The graft member 490 is similar in construction to the valve memberdescribed in the various valve device embodiments described above,except that the graft member 490 is attached to the support frame 410 ina manner that substantially closes the open cell 418 defined by theclosed circumference 416. Thus, the edge 492 of the graft member 490 isattached to the support frame 410 around substantially the entire closedcircumference 416. Similar to the valve embodiment, sutures 494 or othersuitable means for attaching a graft member to a support frame can beused to form the desired attachment.

As a result of the closing of the open cell 418, the occluder 400, whendeployed in a body vessel, can substantially block fluid flow throughthe body vessel at the point of deployment. This effect may be desirablein various clinical situations, including the treatment of tumors,arteriovenous malformations (AVM's), and other situations in which it isdesirable to block the flow of blood or other fluid to a particularsite.

FIGS. 18 and 19 illustrate another exemplary valve device 500. The valvedevice 500 of this embodiment is similar to the valve device 300illustrated in FIGS. 15 through 17 and described above, except asdetailed below.

The valve device 500 according to this embodiment includes a supportframe 510 and an attached bioprosthetic valve 550. The support frame 510includes first 512 and second 514 wire members. The first wire member512 includes a first end 512 a and a second end 512 b. The wire member512 defines an arcuate path that includes a curve disposed substantiallyat a midpoint between the first 512 a and second 512 b ends. Similarly,the second wire member 514 includes first 514 a and second 514 b endsand defines an arcuate path that includes a curve disposed substantiallyat a midpoint between the ends 514 a, 514 b. The wire members 512, 514cooperatively define a closed circumference 516 that, in turn, defines asingle closed cell 518.

The wire members 512, 514 of the support frame 510 comprise a unitarystructure that has been cut from a tube, such as from a nitinol tube.Thus, the support frame 510 lacks the connectors described above and,instead, the wire members 512, 514 simply meet and join at theirrespective ends. A first plurality of barbs 528 is disposed at a firstend of the support frame 510, and a second plurality of barbs 530 isdisposed at a second end of the support frame. As illustrated in theFigure, the each barb of the plurality of barbs 528, 530 isadvantageously adapted to pass into a partial thickness of a wall 562 ofa body vessel 560 in which the valve device 500 is deployed.

The support frame 510 includes first 540 and second 542 support armsdefined by the respective wire member 512, 514. In this embodiment, eachof the support arms 540, 542 is an open curve that defines a partial,elongated loop in the respective wire member 512, 514 of the supportframe 510.

The bioprosthetic valve can comprise any suitable bioprosthetic valve,and the specific bioprosthetic valve selected for a valve deviceaccording to a particular embodiment will depend on variousconsiderations, including the body vessel into which the valve device isintended to be implanted. Examples of suitable bioprosthetic valvesinclude those describe in U.S. Provisional Application Ser. No.60/980,770, which is hereby incorporated into this disclosure in itsentirety. The bioprosthetic valve 550 is similar to the bioprostheticvalves described therein, and will be described herein only briefly. Thebioprosthetic valve 550 includes a patch 552 of tissue connected to asingle leaflet 554. The leaflet 554 has a free edge 556 that moves inresponse to differing pressures in the body vessel 560, or othersuitable environmental changes, to open and close the valve device 500and to selectively permit antegrade fluid flow, represented by arrow 575in FIG. 13, and substantially prevent retrograde fluid flow, representedby arrow 585 in FIG. 14, through the body vessel 560.

While tissue valves and sheet form valve members can be used with thesupport frames according to the disclosure, the support frame 510illustrated in FIGS. 18 and 19 is particularly well-suited for use withsingle leaflet bioprosthetic valves, such as the bioprosthetic valve 550illustrated in FIGS. 18 and 19, at least because of the curvilinearattachment pathway provided by the arms 540, 542, which provides apocket definition function believed to be critical for the formation ofa functional valve from a single leaflet-containing bioprosthetic valve.

The bioprosthetic valve 550 is attached to one end of the support frame510, using sutures or any other suitable means for attaching tissue to asupport frame. The leaflet 554 is advantageously attached to the wiremembers 512, 514 along an attachment pathway that extends alongsubstantially the entire length of the open curve defined by the arms540, 542, although shorter and longer attachment pathways can be used.As illustrated in FIGS. 18 and 19, this produces a curvilinearattachment pathway 570. Also as illustrated in FIGS. 18 and 19, it isconsidered particularly advantageous for the attachment pathway toinclude the apex 572 of the curves defined by the arms 540, 542, as thisis expected to increase the overall ruggedness of the attachment betweenthe leaflet 554 and the frame 510 in the dynamic environment of a bodyvessel 560. Examples of other suitable means for attaching a tissuevalve and/or a tissue to a support frame include clips, staples,adhesives, and tissue welding materials and techniques. As bestillustrated in FIG. 19, the free edge 556 of the leaflet 554 issubstantially free of the support frame 510 and extends between the arms540, 542, allowing the free edge 556 to move within the confines of thewire members 512, 514 to effect opening and closing of the valve device500.

Any suitable tissue can be used to form a bioprosthetic valve for use ina valve device according to an embodiment of the invention. The tissueselected for a bioprosthetic valve in a device according to a particularembodiment of the invention need only be capable of being attached tothe support frame in a manner that forms the desired valveconfiguration. The tissue should be selected to provide desirablebehavior of the valve following deployment of the biomedical valvedevice in a body vessel. Examples of suitable tissues include pleura,such as a lining from the peritoneal cavity, a tissue capsule, such as arenal capsule, and a vessel wall or portion thereof. The use of tissuesother than vessel walls might be particularly advantageous whenfashioning a biomedical valve device according to an embodiment of theinvention that is intended to be implanted in a patient that is missinga particular body vessel or has a damaged portion of a particular bodyvessel. For example, in humans that have already lost a greatersaphenous or other donor vessel, use of a renal capsule or other tissuemight be advantageous.

FIG. 18 illustrates the valve device 500 in a closed configuration, inwhich the leaflet 554 has substantially opened to define a valve pocket558 between the leaflet 554 and patch 552 that substantially preventsretrograde fluid flow, represented by arrow 585, from passing throughthe body vessel 560. The leaflet free edge 556 has been forced outwardlyby retrograde fluid flow 585, substantially forcing the free edge 556away from the patch 552 and allowing the valve pocket 558 to open. Overtime, the valve pocket 558 fills with fluid until antegrade fluid flowor other forces, such as a change in the pressure differential acrossthe valve device 500, favors a transition to the open configuration, asillustrated in FIG. 18 and described above.

FIG. 19 illustrates the valve device 500 in an open configuration, inwhich the free edge 556 of the leaflet 554 has been forced inward byantegrade fluid flow 575, which substantially forces portions of theleaflet 554 toward the patch 552. The free edge 556 folds upon itselfand/or other portions of the leaflet 554 when the valve device 500 is inthis configuration, substantially reducing the volume of the valvepocket 558 defined by the leaflet 554 and patch 552. In addition to thefolding action of the leaflet, an elastic transition may take placeprior to, during, and/or after the leaflet folds inward. With abioprosthetic valve, it is believed that the leaflet elasticallycontracts to a certain point, and subsequently folds inward. When thevalve device transitions to the open configuration from a closedconfiguration, described below with reference to FIG. 19, fluid issubstantially forced out of the valve pocket 558, effectively flushingthe valve device 500.

A comparison of the valve device 500 illustrated in FIGS. 18 and 19 tothe valve device 300 illustrated in FIGS. 16 and 17 illustratesdifferent functions for the support arms in the two devices. In valvedevice 300, arms 340, 342 effectively provide a backstop for the valvemember 350 as it moves to the closed configuration, which may assist inthe prevention of prolapse of the valve device 300. In valve device 500,the arms 540, 542 include the additional function of assisting in thedefining of the valve pocket 558. As illustrated in FIGS. 18 and 19, thearms 540, 542 define the lateral boundaries of the valve pocket 558 inboth the open and closed configurations.

FIG. 21 illustrates a support device 600 according to an exemplaryembodiment of the invention. The support device 600 comprises a supportframe 610 that includes first 610 a and second 610 b frame portions.Each frame portion 610 a, 610 b is similar to the support frame 10illustrated in FIG. 1 and described above. Thus, the first frame portion610 a includes first 612 a and second 612 b wire members connected toeach other at opposing ends with connectors 620 a, 620 b. Similarly, thesecond frame portion 612 b includes first 614 a and second 614 b wiremembers connected to each other at opposing ends with connectors 622 a,622 b.

The first wire member 612 a of the first frame portion 610 a and thefirst wire member 614 a of the second frame portion 610 b intersect atintersection 616 a. Similarly, the second wire member 612 b of the firstframe portion 610 a and the second wire member 614 b of the second frameportion 610 b intersect at intersection 616 b. The intersections 616 a,616 b can be a simple crossing of wire members, with optional contactbetween the members, or can comprise a mechanical connection between themembers formed using any suitable means for connecting portions ofsupport frame to each other, including rivets, welds, post and holeconnections, and other suitable structures. A connection that allows therelevant wire members to move relative to each other at the intersection616 a, 616 b is considered advantageous at least because it is expectedto allow the support device 600 to flex in response to movement of a thewall 662 of a body vessel 660 in which the device is implanted.

The support device 600 can be used as a stent to provide intraluminalsupport to a body vessel. Alternatively, as described more fully below,the support device 600 can be used in a valve device or other suitablemedical device.

FIG. 22 illustrates a valve device 700 according to an exemplaryembodiment of the invention. The valve device 700 includes a supportframe 710 and an attached bioprosthetic valve 750. The valve 750 opensand closes to regulate fluid flow through a body vessel 760 in which thedevice 700 is implanted.

The support frame 710 is similar to the support frame 610 illustrated inFIG. 12 and described above. Thus, the support frame 710 includes first710 a and second 710 b frame portions. The first frame portion 710 aincludes first 712 a and second 712 b wire members connected to eachother at opposing ends with connectors 720 a, 720 b. Similarly, thesecond frame portion 712 b includes first 714 a and second 714 b wiremembers connected to each other at opposing ends with connectors 722 a,722 b.

The first wire member 712 a of the first frame portion 710 a and thefirst wire member 714 a of the second frame portion 710 b intersect atintersection 716 a. Similarly, the second wire member 712 b of the firstframe portion 710 a and the second wire member 714 b of the second frameportion 710 b intersect at intersection 716 b.

The bioprosthetic valve 750 includes a patch 752 of tissue connected toa single leaflet 754. The leaflet 754 has a free edge 756 that moves inresponse to differing pressures in the body vessel 760, or othersuitable environmental changes, to regulate fluid flow through the bodyvessel 760.

The bioprosthetic valve 750 is attached to the support frame 710 at oneend of the support frame 710, using sutures or any other suitable meansfor attaching tissue to a support frame. The leaflet 754 issubstantially free of the support frame 710, allowing the free edge 756to move within the confines of the wire members 712, 714.

As described above with reference to FIGS. 11 through 13 and 15 through17, support frames according to the disclosure provide a suitable frameonto which a simple valve member, such as a sheet of material, can beattached to form a functional prosthetic valve. Also, as described abovewith reference to FIGS. 18 and 19, support frames according to thedisclosure provide a suitable frame onto which more complex valvemembers, such as a natural valve harvested from an animal or human, canbe attached to form a functional prosthetic valve device. Furthermore,as illustrated in FIG. 20 and described above, the support framesaccording to the disclosure can be used in other types of medicaldevices as well, such as occluders. As such, the support framesaccording to the disclosure provide a relatively simple platform ontowhich a variety of valve members and other additional elements can beattached to form a wide array of useful medical devices.

While various embodiments are described with reference to specificfeatures of particular drawings, it is understood that the variouselements and/or features described herein in connection with oneparticular embodiment can be combined with those of another withoutdeparting from the scope of the invention. For example, the arms 340,342 of the support frame illustrated in FIG. 15 could be incorporatedinto the support frame 410 of the occluder device 400 illustrated inFIG. 20.

The embodiments described and illustrated herein provide examples of theinvention, and are not intended to limit the scope of the invention inany manner. Rather, they serve only to aid those skilled in the art tomake and use the invention.

1. A low profile medical device for placement within a body vessel, saidmedical device having a lengthwise axis, a radially compressedconfiguration and a radially expanded configuration, said medical devicecomprising: a support frame comprising: a first wire member having firstand second ends and defining a first arcuate path with a first curvedisposed between the first and second ends, the first arcuate pathcomprising only a single sigmoidal curve; a second wire member havingthird and fourth ends and defining a second arcuate path with a secondcurve disposed between the third and fourth ends, the second arcuatepath comprising only a single sigmoidal curve; a first connectorconnecting the first and third ends; and a second connector connectingthe second and fourth ends and spaced from the first connector on saidlengthwise axis of said medical device; wherein substantially no portionof the support frame is disposed on a first transverse axis of saidmedical device opposite the first and third ends and substantially noportion of the support frame is disposed on a second transverse axis ofsaid medical device opposite the second and fourth ends when saidmedical device is in said radially expanded configuration; wherein thefirst and third ends extend along a third axis and the second and fourthends extend along a fourth axis different from the third axis; andwherein the third axis and the fourth axis are substantially parallel tothe lengthwise axis; and a graft member attached to the support frame.2. The low profile medical device of claim 1, wherein the graft membercomprises a flexible sheet of material.
 3. The low profile medicaldevice of claim 1, wherein the graft member comprises a naturalmaterial.
 4. The low profile medical device of claim 3, wherein thegraft member comprises a bioremodellable material.
 5. The low profilemedical device of claim 4, wherein the graft member comprises anextracellular matrix material.
 6. The low profile medical device ofclaim 5, wherein the graft member comprises small intestine submucosa.7. The low profile medical device of claim 3, wherein the graft membercomprises fixed tissue.
 8. The low profile medical device of claim 3,wherein the graft member comprises a tissue valve.
 9. The low profilemedical device of claim 1, wherein the graft member comprises asynthetic material.
 10. The low profile medical device of claim 9,wherein the graft member comprises a polymeric material.
 11. The lowprofile medical device of claim 10, wherein the graft member comprisesexpanded polytetrafluoroethylene.
 12. The low profile medical device ofclaim 10, wherein the graft member comprises polyurethane.
 13. The lowprofile medical device of claim 1, wherein the graft member comprises acombination of natural and synthetic materials.
 14. The low profilemedical device of claim 1, further comprising means for attaching thegraft member to the support frame.
 15. The low profile medical device ofclaim 14, wherein the means for attaching comprises a suture.
 16. Thelow profile medical device of claim 1, wherein the graft member includesan edge and a portion of the edge wraps around a portion of one of thefirst and second wire members.
 17. The low profile medical device ofclaim 1, wherein the graft member includes a first portion attached tothe support frame and a free edge not attached to the support frame;wherein the graft member is moveable between first and second positionswhen said medical device is placed within said body vessel; wherein thegraft member substantially prevents fluid flow through said body vesselin a first direction when the graft member is in the first position; andwherein the graft member permits fluid flow through said body vessel ina second, opposite direction when the graft member is in the secondposition.
 18. The low profile medical device of claim 1, wherein thefirst and second wire members cooperatively define a closedcircumference that defines a cell; and wherein the graft member includesan edge and the edge is attached to the support frame aroundsubstantially the entire closed circumference such that the graft membersubstantially closes the cell.
 19. A low profile medical device forplacement within a body vessel, said medical device having a lengthwiseaxis, a radially compressed configuration and a radially expandedconfiguration, said medical device comprising: a support framecomprising: a first wire member having first and second ends anddefining a first arcuate path with a first curve disposed between thefirst and second ends; a second wire member having third and fourth endsand defining a second arcuate path with a second curve disposed betweenthe third and fourth ends; a first connector connecting the first andthird ends; and a second connector connecting the second and fourth endsand spaced from the first connector on said lengthwise axis of saidmedical device; wherein substantially no portion of the support frame isdisposed on a first transverse axis of said medical device opposite thefirst and third ends and substantially no portion of the support frameis disposed on a second transverse axis of said medical device oppositethe second and fourth ends when said medical device is in said radiallyexpanded configuration; wherein the first and third ends extend along athird axis and the second and fourth ends extend along a fourth axisdifferent from the third axis; and wherein the third axis and the fourthaxis are substantially parallel to the lengthwise axis; and a graftmember having first and second edge portions, the first edge portionattached to the first wire member and extending along a first attachmentpathway that includes the first arcuate path and the second edge portionattached to the second wire member and extending along a secondattachment pathway that includes the second arcuate path.
 20. The lowprofile medical device of claim 19, wherein the graft member comprises afree edge not attached to the support frame.
 21. The low profile medicaldevice of claim 19, wherein the first and second wire memberscooperatively define a closed circumference that defines a cell; andwherein the graft member includes an edge comprising the first andsecond edge portions; and wherein the edge is attached to the supportframe around substantially the entire closed circumference such that thegraft member substantially closes the cell.
 22. A low profile medicaldevice for placement within a body vessel, said medical device having alengthwise axis, a radially compressed configuration and a radiallyexpanded configuration, said medical device comprising: a support framecomprising: a first wire member having first and second ends anddefining a first arcuate path with a first curve disposed between thefirst and second ends, the first arcuate path comprising only a singlesigmoidal curve; a second wire member having third and fourth ends anddefining a second arcuate path with a second curve disposed between thethird and fourth ends, the second arcuate path comprising only a singlesigmoidal curve; a first connector connecting the first and third ends;and a second connector connecting the second and fourth ends and spacedfrom the first connector on said lengthwise axis of said medical device;wherein substantially no portion of the support frame is disposed on afirst transverse axis of said medical device opposite the first andthird ends and substantially no portion of the support frame is disposedon a second transverse axis of said medical device opposite the secondand fourth ends when said medical device is in said radially expandedconfiguration; and a graft member having first and second edge portions,the first edge portion attached to the first wire member and extendingalong a first attachment pathway that includes the first arcuate pathand the second edge portion attached to the second wire member andextending along a second attachment pathway that includes the secondarcuate path.
 23. The low profile medical device of claim 22, whereinthe graft member comprises a free edge not attached to the supportframe.
 24. The low profile medical device of claim 22, wherein the firstand second wire members cooperatively define a closed circumference thatdefines a cell; and wherein the graft member includes an edge comprisingthe first and second edge portions; and wherein the edge is attached tothe support frame around substantially the entire closed circumferencesuch that the graft member substantially closes the cell.